The invention relates to torque steering mitigation for electric power steering (EPS).
In front wheel drive vehicles, imbalances in driveline geometry (e.g. unequal half shaft lengths, different half shaft input angles), can cause an imbalance in driving force applied by the wheels relative to one another. This imbalance in driving force can cause the vehicle to steer. Typically, the imbalance is small and does not cause a change in vehicle direction. However, when large amounts of torque are applied to a road surface, driving force imbalances can be exaggerated, causing a change in direction. For example, the vehicle could pull in one direction during a hard acceleration. This behavior is known as a torque steer.
Torque steer can be separated into two categories including transient and quasi-steady state. Transient torque steer is relatively short in duration and can be difficult to consistently reproduce. Quasi-steady state torque steer is consistent, pulling the same direction and with a force that is related to the driving force of the vehicle.